This invention relates to heat exchangers. Specifically, this invention relates to an improved formed plate heat exchanger construction.
Heat exchangers in general are well known in the prior art, and typically comprise a heat exchanger core having dual fluid flow paths for passage of two fluids in heat exchange relation with each other without intermixing. The fluid flow paths commonly comprise a plurality of relatively small and/or intricately shaped passages formed within a heat exchanger core so as to maximize the available core surface area for absorbing and transferring heat energy from one fluid to another.
In the prior-art, plate-type heat exchangers have become popular largely because of their simplicity of fabrication and ease of assembly. Such plate heat exchangers comprise a stacked array of relatively thin plates connected together in a spaced relationship so as to provide fluid flow regions between the plates. Extended surface fin elements commonly are interposed between the plates to form a multiplicity of relatively small fluid flow paths within the flow regions, and to increase the available surface area for absorbing and transferring heat energy. Suitable manifolds supply the two fluids to the heat exchanger for flow through the flow paths in the core without intermixing.
Plate-type heat exchangers of the prior art typically display certain disadvantages which limit their utility to relatively high technology applications. In particular, these heat exchangers require a variety of parts such as plates, fins, headers, and the like which must be carefully and accurately positioned and secured together for proper operation of the heat exchanger. See, for example, U.S. Pat. No. 2,804,284. Moreover, the plate materials are desirably thin to form a lightweight heat exchanger core with maximum heat transfer between fluids. However, the use of lightweight plates is limited by the capacity of the assembled core to endure mechanical shear loads and thermal cycling stresses without collapsing, stress failure, etc. See, for example, U.S. Pat. Nos. 1,914,077, 2,375,702, 3,463,222, 3,661,203 and 3,705,618.
The heat exchanger of this invention overcomes the problems and disadvantages of the prior art by providing an improved plate-type heat exchanger formed from a minimum number of parts, and including interfitting formed plates providing a rigid heat exchanger construction of three dimensional stability.